Guaranteeing the ownership or copyright of digital communication is of extreme importance in this digital era. Watermarking is the technique which confirms the authenticity or integrity of communication by hiding relevant information in specified areas of the original signal such that it might render it difficult to distinguish one from the other. Thus, the digital watermark can be defined as a type of indicator secretly embedded in a noise tolerant signal such as image, audio or video data.

The paper presents a voice signal authentication scheme by employing signal features towards the preparation of the watermark and by embedding it in the transform domain with the Walsh transforms. Watermark used in this technique is unique for each member participating in this communication system and makes it is very imperative in the context of signal authentication.

Most organizations concurrently maintain private Automatic Branch Exchange (PABX) and Local Area Network (LAN) for information interchange within their organization. This is obviously a waste of resources and avoidable duplication of communication systems. The existing LAN can be used as a communication backbone for the in house telephone operations with no extra cost and resources. In view of this, a portable and a platform independent Software-Based Cell Phone (SCP) was proposed for the existing LANs infrastructure in the organizations.

The SPC is a telephony application with a user friendly interface which is capable of handling voice, video and text messages without compromising the Quality of Service (QoS) of the existing LAN.

Task scheduling is an important factor that directly influences the performance and efficiency of the system. Grid computing utilizes the distributed heterogeneous resources in order to support complicated computing problems. Grid can be classified into two types: computing grid and data grid. Job scheduling in computing grid is a very important problem. To utilize grids efficiently, we need a good job scheduling algorithm to assign jobs to resources in grids. This paper presents a new algorithm based on ant colony optimization (ACO) metaheuristic for solving this problem. In this study, a proposed ACO algorithm for scheduling in Grid systems will be presented. Simulation results indicate our ACO algorithm optimizes total response time and also it increase utilization.

The IEEE 802.11 WLAN is primarily used for web browsing which belongs to the category of non-real time application. But the demand of real time applications like VOIP and video conferencing has become very much common to such WLAN. With IEEE 802.11e Mac protocol it is possible to improve the QoS for both real and non-real time traffic by service differentiation. To ensure efficient utilization of the radio resources and enhanced QoS the load imbalance should be resolved among APs from different BSSs. In large scale WLAN inter AP communication mechanism can be employed along side the current admission controller under EDCA. Beside service differentiation inter AP differentiation based QoS management can lead to efficient utilization of radio resources by moving STAs from heavily laded to a less loaded AP and ensure better QoS for all types of traffics. In this paper we propose a dynamic and fair AP selection mechanism to improve the QoS in a WLAN. The simulations have been carried out with NSv2.34.

Mobile Ad hoc Networks are wireless infrastructure less networks can be easily formed or deployed due to its simple infrastructure. Security has become a primary concern in order to provide protected communication between mobile nodes in a hostile environment. The main objective of this work is to enhance the performance of the network by securing the data and to minimize the malicious nodes which disturb the stream of the network. Securing data is a critical task which can be achieved by cryptographic algorithms and disturbance detection plays as a crucial ingredient in any comprehensive security solution to address the threats. Hence a Novel Cryptographic Algorithm with a new Disturbance Detection System (DDS) has been proposed for Mobile Adhoc Networks. This method prevents the outside attacks to obtain any information from any data exchange in network and also use promiscuous mode of working along with rating and collaborative decision making based on multiple threshold values. The proposed algorithm was implemented and simulated in the Glomosim and the result analysis proved that the performance of the network is increased.

An ad hoc network is a mobile wireless network that has no fixed access point or centralized infrastructure. Each node in the network functions as a mobile router of data packets for other nodes and should maintain the network routes for long standing which is not possible due to limited battery source. Also, due to node mobility, link failures in such networks are very frequent and render certain standard protocols inefficient resulting in wastage of power and loss in throughput. The power consumption is an important issue with the goal to maintain the network lives for long by consuming less power. The power consumption can be achieved by modifying algorithms such as cryptographic algorithms,Routing algorithms, Multicast Algorithms, Energy Efficient Algorithms and Power Consumption Techniques in High Performance Computing, Compression and decompression algorithms, minimizing link failure algorithms, and by power control algorithms. In this work, we have proposed a new algorithm for minimization of power consumption in Ad hoc networks. The performance of the proposed model is analyzed and it is observed that, information could be sent with security consuminglesscomputational power, thereby increasing the battery life.

One of the major developments in machine learning in the past decade is the ensemble method, which finds highly accurate classifier by combining many moderately accurate component classifiers. In this research work, new ensemble classification methods are proposed for homogeneous ensemble classifiers using bagging and heterogeneous ensemble classifiers using arcing classifier and their performances are analyzed in terms of accuracy. A Classifier ensemble is designed using Radial Basis Function (RBF) and Support Vector Machine (SVM) as base classifiers. The feasibility and the benefits of the proposed approaches are demonstrated by the means of real and benchmark data sets of intrusion detection. The main originality of the proposed approach is based on three main parts:  preprocessing phase, classification phase and combining phase. A wide range of comparative experiments are conducted for real and benchmark data sets of intrusion detection. The accuracy of base classifiers is compared with homogeneous and heterogeneous models for data mining problem. The proposed ensemble methods provide significant improvement of accuracy compared to individual classifiers and also heterogeneous models exhibit better results than homogeneous models for real and benchmark data sets of intrusion detection.

Conventional visual secret sharing schemes generate noise-like random pixels on shares to hide secret images. It suffers a management problem, because of which dealers cannot visually identify each share. This problem is solved by the Extended Visual Cryptography scheme (EVCS). However, the previous approaches involving the EVCS for general access structures suffer from a low contrast problem. This paper proposes a new (k,n)-threshold image sharing scheme using extended visual cryptography scheme for color images based on bit plane encoding that encrypts a  color image in such a way that results of encryption is in the form of shares. Shares do not reflect any information directly, information is scrambled instead. The traditional binary EVCS is used to get the sharing images at every bit level of each principle component of a color image. This scheme provides a more efficient way to hide natural images in different shares. Furthermore, the size of the hidden secret can be recovered by inspecting the blocks in the shares. This new scheme for color images gives the ideal contrast in the recovered image.